Conventionally, a so-called cavity circuit board is known which is configured by bonding an upper-layer board member to the upper surface of a lower-layer board member, and in which an electrode pattern is formed on the upper surface of the circuit board, and the bottom surfaces of openings (cavity portions) disposed in a part of the upper surface, and such a circuit board is used in various apparatuses as a lightweight and high-density circuit board as a lightweight and high-density circuit board (Patent Reference 1).
In a screen printing device which performs screen printing of a paste such as a solder paste on each of the both electrode patterns of such a cavity circuit board, a three-dimensional mask member is used which has a planar portion that is to be contacted with the upper surface of the circuit board, and fitting portions that are projected from the planar portion to be fitted to the cavity portions. In the mask member, a mask pattern corresponding to an electrode pattern (flat-portion electrode pattern) disposed on the upper surface of the circuit board is formed in the planar portion, and that corresponding to an electrode pattern (cavity-portion electrode pattern) disposed on the bottom surfaces of the cavity portions is formed on the bottom surfaces of the fitting portions. When screen printing is performed while the circuit board and the mask member are contacted with each other, therefore, a paste can be printed (transferred) simultaneously onto both the flat-portion electrode pattern and the cavity-portion electrode pattern.